Originally Posted by stux
Full volume BIAB efficiency is directly dependent on the liquor:grain ratio in the mash.
Not sure of the exact curve, but as your l:g ratio drops the mash gravity increase, and as the grain absorption remains constant (by weight) you lose relatively more sugars. This is basically a "lautering loss"
Think it's time I ran the numbers and made a chart
I ran the numbers and made a chart
My discussion on this chart : http://www.biabrewer.info/viewtopic.php?f=74&t=1481
Basically, I've graphed the Lautering Loss as a percentage vs Liquor to Grain Ratio for four True Absorption values.
1.2 L/KG = BIAB Heavy Squeeze
1.3 L/KG = BIAB Medium Squeeze
1.4 L/KG = BIAB Light Squeeze
1.56 L/KG = Traditional Mash Tun
As modelled using my Conversion Efficiency formulas, which have been quite successful in modelling the BIAB process
This is for No Sparge. You can see why a sparge makes a big difference when the L:G is low.